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Paints, Stains and Coatings
MAINTENANCE MATTERSBuilding Maintenance Bulletin
Paints, Stains and Coatings
February 2018
MAINTENANCE MATTERS
Number 1
1
Maintenance MattersThis series of bulletins and
companion videos is designed to
provide practical information on
maintaining residential buildings.
Produced by BC Housing, in
collaboration with Polygon and
the Condominium Home Owners’
Association (CHOA), this bulletin
was prepared by a consortium of
building envelope experts.
Have you ever noticed how a building shows its age? A new
building looks clean, the exterior isn’t faded, the wood trim is
in perfect shape, metal parts are not rusted or scratched, and
it even smells new. As the new appearance disappears, so
does the protection provided by paints, stains and coatings.
To make sure your building does not fall into disrepair, you have to know
what types of paint and coating protection your home has, why it must be
maintained, how and how often to maintain it, and who to call. You also need
a written plan to maintain the surfaces that protect your home’s appearance
and condition. Often, it is realized that a maintenance plan is needed for paints,
stains and coatings when it is too late and damage has already occurred. The
purpose of this bulletin is to highlight maintenance issues and provide basic
information to help prevent avoidable and expensive problems.
Note: This bulletin discusses the maintenance of paints, stains and coatings
related to the exterior surfaces of the building envelope. It does not cover
maintenance or re-painting for home interiors.
What are Paints, Stains and Coatings and Where are They Applied?
There are many different types of paints, stains and coatings used to cover the
various surfaces of the building envelope. Paints, stains and coatings improve
the visual appearance of the building, protect the underlying surface (wood,
metal, concrete, stucco or plastic) from the damaging effects of the sun, wind
and rain. They also help prevent decay and corrosion from occurring.
The appropriate product must be used for each application or you will not get the
protection the building needs to keep looking new and in good physical condition.
Paint peeling from a metal flashing: Good quality factory-finished metals have better endurance than this site-painted metal flashing.
2 Maintenance Matters No. 1
Paints, Stains and Coatings
The table below lists different types of paints, stains and
coatings and where they are commonly applied.
Why Must Paints, Stains and Coatings be Maintained?
Paints, stains and coatings don’t last forever and must be
maintained and restored when they have deteriorated due
to exposure to the sun, rain, hot and cold temperatures,
bird activity, people-inflicted damage and other
destructive forces.
Paint, Stain or Coating Where Applied
Asphaltic paints and dampproofing
Brick, concrete foundations, iron and steel in covered areas for water resistance
Concrete floor paints Interior or protected concrete floors
Clear finishes When the natural beauty of wood or other product is not hidden
Enamel (oil based paint) Siding, wood and metal trim
Latex Siding, wood trim, stucco
Powder coating Metal balcony railings, door parts, gutters, metal flashing
Rust inhibiter paints Steel components
Stains Wood or other product where appearance is not hidden
Waterproofing Where water pressure will build up against the surface
Water repellant Where water must not be absorbed or seep through
Ultra-violet inhibitor paint
Where a clear finish is used, especially outdoors
An aging and neglected building typically displays many reasons why you should maintain paints, stains and coatings in a timely fashion. This includes:
› Appearance: The colours are faded and not consistent due to exposure to the ultra-violet rays of the sun. Flakes and blisters can occur making the building even less appealing.
› Wetting and drying of the building parts: Wood that is not protected by paint or stain swells and shrinks, resulting in cracking and possibly water entry further into the wall.
› Damage to the siding and trim: When wood becomes thoroughly weathered, it loses its strength and flexibility resulting in irreparable cracks. When wetness is sustained, wood will decay.
› Corrosion: When not protected, steel components will corrode (steel flakes and is rust coloured), lose strength and their new appearance.
If re-painting or re-staining of wood is left too long, permanent damage can occur. At that point, the application of paints, stains and coatings will not address the damage done.
When steel corrodes, some of its shape and strength is permanently lost. Some building components such as flashings, screws, nails and bolts cannot afford to lose their strength.
What Maintenance Must be Performed?
You should notify the maintenance manager if you believe there is a maintenance problem with the paints, stains or coatings. Your maintenance manager should keep a log of inspections and complaints as well as a history of maintenance work. Maintenance and re-painting concerns should be acted on promptly. If neglected, they have the potential to damage underlying materials.
The exterior finish of the building should be checked annually by a qualified painter for blisters, loose paint, thin or worn paint coatings, scratches or punctures. These issues can permit water to be absorbed into the porous components and lead to damage.
Maintenance Matters No. 1 3
1 IntroductionPaints, Stains and Coatings
If there are any unusual maintenance issues or you have any doubts as to the proper approach for specific requirements for your building, obtain professional advice from a building envelope consultant.
It is important to select a professional applicator with a good track record on other buildings with the same cladding (wood siding or stucco, for example) as your own.
How Often is Re-Painting, Re-Staining or Re-Coating Necessary?
The wood siding or trim on most residential buildings
should be re-painted every five to seven years, for the
average building with average weather exposure, or even
sooner if problems become apparent.
Some areas of the building may require painting more
frequently than others. For example, in the south-west of
British Columbia it is common for the predominant wind-
driven rainstorms to attack buildings from the south and
east. Sun exposure also has the greatest effect on these
sides, so it is likely that they will require re-painting more
often than the north or perhaps west sides. Hence, “one-
size-fits-all” advice on how often to re-paint may not be
appropriate for your building.
Stucco, fibre-cement siding, metal and plastic sidings
can also be painted. These materials are less absorbent
and typically less vulnerable to problems than wood
once their paint or coating has been depleted by the elements. They, therefore, require less regular re-painting to maintain their durability and resistance to weather. Manufacturer’s recommended maintenance information should be kept on hand. If the manufacturer’s advice is not followed, there is a good chance that the warranty on the product would be void if a problem arises. Fibre-cement siding companies have quite specific advice on when and how often their product should be painted and what type of paint to use. Applying latex paint to certain metals can promote corrosion rather than prevent it. For these reasons, maintenance of paints, stains and coatings must consider product compatibility information supplied by the manufacturer.
As a general rule, you should re-paint or re-apply a coating when the previous application is just beginning to show signs of deterioration, before it loses its ability to protect the material.
Separate from the annual review of the paint, check the condition of the underlying components, like the wood, every three to four years.
The table below provides some basic information about what to look for when deciding when to paint next. Note that in addition to reviewing the condition of the paint, stain or coating, it is also important to review the condition of the underlying materials, like wood. There is
no point in re-coating a material that is already damaged.
Some coatings such as this acrylic stucco coating over tar-based damp-proofing are incompatible, resulting in a cosmetic detraction instead of providing protection.
This wood siding has suffered irreparable, permanent damage that cannot be corrected by further paint or stain application. This could have been prevented through proper maintenance.
Coatings will not remain adhered if water is permitted to absorb into the material it is intended to protect. As shown here, coating can peel when this occurs.
4 Maintenance Matters No. 1
Paints, Stains and Coatings
Who Should be Called for Service?
The value of painting qualifications is often under-
estimated.
If your building’s exterior needs re-painting or re-coating, it
is in a vulnerable state and perhaps already deteriorating.
It is worth getting the best advice and service available
to give it the protection it needs. An experienced painting
contractor, building envelope consultant or member of
the Master Painters and Decorators Association has the
knowledge and expertise to determine:
• if painting or re-coating is required now, or when it will
be required
• what sort of preparation is required
• what sort of paint is used and how it is applied
• roughly how much the project will cost
• which surfaces should be painted and which require
cleaning only
What is the Process?
Re-painting your building should be done by a professional
contractor. The following section describes the painting
process and what to expect.
Preparation
Re-painting requires preparation. The type of preparation
required depends on the condition of the original paint
and the material itself. In the case of paints and stains, an
ounce of prevention is worth much more than a pound of
cure. If paint is still relatively new (three to five years), in
most cases it can be lightly sanded or wire-brushed and
a fresh coat of paint applied over the old. This is only true
if the original paint is well bonded to the wood or metal
in which it was applied and if the wood or metal is still
dry and in good condition.
If water has saturated the painted material, it is likely
that the paint has loosened. If this is the case, the wood
must be stripped, permitted to dry and may even have
to be replaced if it is damaged. The situation with rusted
steel is similar. Rust flakes will lift the paint off of the steel
surface, requiring removal of the old paint and rust prior
to re-painting.
Year What to Look for
The first year (or two) after painting or new construction
Painting or coating deficiencies: poorly-applied areas that don’t hide the painted component, cracked paint, blistered paint from being applied to wet material, poor detailing, overspray, etc.
Years three to five Colour fading, chalking of the surface, loose paint areas, damage. Look for patterns in the weathering. In other words, start planning for a partial re-painting (in more sun exposed areas) or general re-painting. Also check the condition of the underlying components, like wood.
Years five to seven If the building hasn’t been re-painted yet, it is defying the odds. At minimum a close critical look by a professional would probably determine that the building exterior is ready to be re-painted as a preventative measure.
Seven years or more past the previous painting
Soft spots in the wood, cracks or blisters in the paint, extreme fading; any of these require prepa-ration and re-painting. Repair of damaged areas may be necessary. Stucco, fibre-cement siding, metal and plastic sidings may likely require re-painting by year 10.
Cleaning and scraping of stucco walls before applying new paint.
1 IntroductionPaints, Stains and Coatings
Seasonal Considerations
It is wise to schedule a major re-painting project in the late
spring or early autumn when temperatures are not expected
to be extreme. Paints and coatings are temperature-
sensitive when being applied. Check the manufacturer’s
directions for application temperature because they vary.
For example, most water-based or latex paints should not
be applied when it is cold (below about 7 degrees Celsius)
because they will not harden. They should also not be
applied when it is too hot (above 35 degrees) with low
humidity because the paint can dry to a powder before it
has time to cure and form the protective film desired.
Special Considerations:
ComponentsSome parts of your home may have been coated in
a factory and may require removal and re-coating in
a factory with special processes not available to the
homeowner or average paint contractor. Examples include
metal doors, railings, some metal flashing and fixtures.
Moving and sliding components like window sash
perimeters and weather seals, should not be painted.
The paint will most likely be damaged on first use or their
operation will be restricted in some way.
Action Plan Tips
• Budget and tentatively plan to re-paint or re-stain
wooden materials every five to seven years (seven to
10 years for stucco, fibre-cement siding, metal or plastic
siding), unless problems are detected sooner. The plan
should be scheduled with those designated to perform
the service. Follow the building’s maintenance manual if
it exists.
• Contact an experienced painting contractor, building
envelope consultant or member of the Master Painters
and Decorators Association to get the best advice and
service available on painting or re-coating your building.
• Annually, a qualified painter should check the entire
exterior for blisters, loose paint, thin or worn paint
coatings, scratches or punctures that permit water to
be absorbed into the porous components, or fading
and chalking (erosion) of the surface.
• Select a professional applicator with a good track
record on other buildings with the same cladding
(wood siding or stucco, for example) as your own.
More Information
The manufacturer’s information is crucial in maintaining
paints, stains and coatings. Other sources of information
will increase your understanding.
› The Master Painters Institute Painting Specification Manual, available at www.paintinfo.com
› Building Enclosure Design Guide – Wood-Frame Multi-Unit Residential Buildings, available at www.bchousing.org
› Your building’s maintenance manual
› Subscribe to receive Maintenance Matters bulletins at www.bchousing.org
1701-4555 Kingsway, Burnaby, BC V5H 4V8
Email: [email protected] www.bchousing.org
Phone: 778-452-6482 Toll-free: 1-866-465-6873
©2020 BC H
ousing
Notice to ReadersThis bulletin is intended to provide readers with general information only. Issues and problems related to buildings and construction arecomplicated and may have a variety of causes. Readers are urged not to rely simply on this bulletin and to consult with appropriate and reputa-ble professionals and construction specialists before taking any specific action. The authors, contributors, funders, and publishers assume no liability for the accuracy of the statements made or for any damage, loss, injury or expense that may be incurred or suffered as a result of the use of or reliance on the contents of this bulletin. The views expressed do not necessarily represent those of individual contributors or BC Housing.The regulations under the Homeowner Protection Act contain specific
provisions requiring owners to mitigate and restrict damage to their homes and permitting warranty providers to exclude coverage for damage caused or made worse by negligent or improper maintenance. These apply to both new and building envelope renovated homes covered by home warranty insurance. Failure to carry out proper mainte-nance or carrying out improper maintenance either yourself or through qualified or unqualified personnel may negatively affect your warranty coverage. It is important for the property owner to read and review their warranty documents to understand how to file any claims and correspondence in the proper written form directly with the warranty company. Refer to your home warranty insurance documentation or contact your warranty insurance provider for more information.